Die holder assembly



July 25, 1967 c. F. KEEN DIE HOLDER ASSEMBDY 2 Sheets-Sheet 1 Filed Oct. 19, 1965 INVENTOR CHARLES E. KEEN lZm/am ATTORNEY July 25, 1967 c. F. KEEN DIE HOLDER ASSEMBLY 2 Sheets-Sheet 2 Filed Oct- 19, 1965 Z2 INVENTOR CHARLES F. KEEN ATTOR NE Y United States Patent 3,332,308 DIE HOLDER ASSEMBLY Charles F. Keen, 315 N. th St., Madison, Wis. 53704 Filed Oct. 19, 1965, Ser. No. 497,914 6 Claims. (Cl. 83-637) This invention relates to die holders, and particularly to a die holder assembly that is adapted to be afiixed to the stationary bed and reciprocating head of a punch press and which will facilely removably receive uniform punch and die plates which can mount a multiplicity of cooperating punches and dies.

Normally cooperating punches and dies are mounted on standard die sets that include a lower die holder to which a die is permanently affixed, an upper punch holder to which a punch is permanently affixed, and upright guide posts secured to the die holder and journaled in openings in the punch holder. The die holder is clamped to the stationary bed of the punch press and the punch holder has a central trunnion that is received in a vise carried by the reciprocating head of the press. It is necessary to have such a standard die set for each punch and die assembly and thus the standard die sets, which are expensive, are in use only when the punch and die mounted thereon are required to be used. At other times the standard die sets stand idle. The time required to mount a standard die set on a punch press for proper alignment of the punch and die is considerable, possibly twenty minutes to a half hour.

Because of the difficulties and expense of using standard die sets, it has been proposed to provide means for quickly attaching and removing punches and dies on punch presses without the use of die sets. These suggestions have generally taken the approach of providing quick operating releasable clamps to clamp plates mounting the punches and dies to the bed and head of the punch press. However, because of the necessity of precise alignment of the punches and dies such quick clamping devices have been quite complex in their construction and require either a specific form of punch press or extensive modification of a punch press to accommodate them.

A die holder assembly in accordance with this invention is comprised of a pair of die and punch holders that are adapted to be secured to the bed and head of a punch press. The holders include means for insuring alignment therebetween as the head reciprocates. The holders each include spaced guide blocks, clamping members mounted on and overhanging the guide blocks, and a stop between the guide blocks and adjacent one end thereof. The punches and dies are mounted on plates of uniform shape and size which may be slipped between the guide blocks, against the stop, and beneath the clamping members. In this manner the plates are accurately aligned in the holders and the clamping members can restrain the plates against the holders. Releasable locking means may also be provided to prevent the plates from slipping away from the stops, and thus out of proper alignment, during the operation of the punch press.

It is the principal object of this invention to provide a simple and inexpensive die holder assembly that is adapted to be employed in a punch press with negligible modification of the press and which will rapidly receive and accurately align interchangeable uniform plates that mount cooperating punches and dies.

It is another object of this invention to provide such a die holder assembly which will accept simple fiat, rectangular plates that mount the punches and dies.

It is a further object of this invention to provide such a die holder assembly in which the uniform plates are abutted by the holder assembly on three sides for accurate alignment of the punches and dies.

It is also an object of this invention to provide such a die holder assembly which easily and quickly locks the uniform plates into proper aligned position on the punch press.

The foregoing and other objects and advantages of the invention will appear in the description which follows. In the description reference is made to the accompanying drawings which form a part hereof and in which there is shown a preferred embodiment of the invention. The preferred embodiment is described in sufiicient detail to enable those skilled in the art to practice the invention but it should be understood that structural changes can be made in the preferred embodiment without departing from the scope of the invention.

In the drawings:

FIG. 1 is a view in front elevation of a die holder assembly in accordance with the invention shown mounted in a punch press and holding a punch and die;

FIG. 2 is a top plan view of the lower die holder of FIG. 1;

FIG. 3 is a view in perspective of the lower die holder of FIG. 2 with the die removed;

FIG. 4 is a view in vertical section the line 44 of FIG. 2; and

FIG. 5 is a view in perspective of a fixture for aligning the die holder assemblies.

Generally, the die holder assembly includes a die holder 10 and a punch holder 11 adapted to be mounted on the stationary bed 12 and reciprocating head 13, respectively, of a punch press. Each of the holders 10 and 11 includes a base plate 14 which is preferably bolted to the head 13 to secure the punch holder 11 thereto and which may be bolted or held by clamps 15 to secure the die holder 10 to the bed 12.

The die holder 10 has a pair of parallel, upright guide pins 16 mounted on its base plate 15 adjacent the rear edge thereof. The base plate 15 of the punch holder 11 is provided with a pair of spaced openings that receive bushings 17 through which the guide pins 16 are journaled, as in well known standard die sets, to maintain alignment between the holders 10 and 11 during operation of the punch press. Except for the provision of guide pins 16 in one of the holders and cooperatnig bushings 17 in the other holder, the die holder 10 and punch holder 11 are identical.

The base plates 14 each have a planar medial surface 18 that is bounded on opposite sides by parallel vertical faces 19. A pair of precision guide blocks 20 and 21 are mounted on each base plate 14. The guide blocks 20 and 21 are located to rest upon a medial surface 18 and against a vertical face 19. The positions of the guide blocks 20 and 21 are controlled by locating pins 22 which extend from the base plates 14 in two parallel rows and which are fitted into aligned bores in the base plates 14 taken in the plane of and guide blocks 20 and 21 (see FIG. 4). The guide.

blocks 20 and 21 are secured in place by recessed machine screws 23 extending through the base plates 14 and by.

machine screws 24 whose heads bear against the guide blocks 20 and 21 and are threadedly received in the base plates 14.

A pair of clamping plates 25 and 26 are provided for each holder 10 and 11. The clamping plates 25 and 26 are disposed on the guide blocks 20 and 21, and are of a width greater than that of the guide blocks so that they project beyond the guide blocks 20 and 21 and overlie the medial surfaces 18 of the base plates 14. The clamping plates 25 and 26 have bores 27 which receive the heads of the machine screws 24 to locate the clamping plates on the guide blocks. The clamping plates 25 and 26 are each held in place by a hexagonal headed bolt 27 that extends through bores in the clamping plate and the guide block to be threadedly received in the base plate 14. A precision stop in the form of a cylindrical member 28 is mounted on the medial surface 18 of each of the holders 10 and 11 between the guide blocks 20 and 21 and adjacent the rear limits thereof.

The holders 10 and 11 are adapted to receive interchangeable, uniform rectangular plates 29 upon which are mounted or formed the dies and cooperating punches; for example, the die 30 and punch 31. Because of the necessity of accurately positioning the dies and punches relative to each other, the die uniform plates 29 must be accurately and precisely positioned in the holders 10 and 11. To this end, the guide blocks 20 and 21 are provided with square corners and precision ground parallel sides, and the location of the guide blocks 20 and 21 and the cylindrical members 28 is the same on each holder 10 and 11. The guide blocks and the cylindrical members 28 define three sides of a rectangle which coincides in dimensions with the plates 29. The plates 29, in turn, have flat parallel sides and square corners. Thus, the plates 29 may be slipped into the holders 10 and 11 by passing them between the guide blocks 20 and 21 and between the clamping plates 25 and 26 and the base plates 14. When the plates 29 have been seated rearwardly to engage the cylindrical members 28, they will then be in proper aligned position.

Accidental withdrawal of the punch and die plates is prevented by locking means formed in conjunction with the guide blocks 20 which are longer than the other guide blocks. The locking means for each holder includes a rod 32 that is loosely fitted within a transverse bore 33 through the guide blocks 20 and is tapered at its end which projects toward the other guide block 21. Adjacent its other end, the rod 32 has a slot that receives a spring steel lever 34 that is anchored at one end on a stud 35 extending from a side of the guide block 20. The spring lever 34 extends forwardly beyond the guide block 20 so that it may be grasped and moved away from the guide block 20 to withdraw the rod within the bore 33 and thereby remove the obstruction which it normally presents. The tapered end of the rod 32 also permits it to be forced into the bore 33 by a plate 29 being inserted in the holder. The normal position of the rod 32 locks the plates 29 against the cylindrical members 28.

To insure that the die 30 and punch 31 will perfectly mate when the plates 29 on which they are formed are mounted in the holders 10 and 11, an alignment fixture as shown in FIG. is employed to align all die holder assemblies used in a shop. The fixture includes upper and lower plates 36 and 37 joined by a cylindrical sleeve 38. The upper and lower plates 36 and 37 duplicate in size and shape the uniform plates 29. Before each die holder assembly is mounted on a punch press in the shop or on a test stand in the tool room, the fixture is secured in the die holder assembly and the assembly is then secured to the press. Thus, when the punches and dies are constructed and aligned in the die holder assembly in the tool room, the insertion of such punches and dies with their uniform plates 29 into the die holder assembly of any punch press will automatically align the punches and dies.

It will be seen from the above description that a die holder assembly in accordance with the invention provides a simple means for accommodating in accurate alignment an unlimited variety of punches and dies mounted on uniform plates. The uniform plates are simple rectangles without complex configuration. For short runs, the clamp ing plates need not be completely tightened and it is necessary only to open the locking means to remove one set of punches and dies and replace it with another. For longer runs, the clamping plates are tightened down securely by bolts 27. The plates 29 are preferably longer than they are wide to prevent their incorrect insertion in 4 the holders 10 and 11. The holders 10 and 11 may be provided with openings for removing the scrap metal from the punch and for permitting the stamped part to fall through as with standard forms of die holders.

I claim:

1. In a die holder assembly adapted for the mounting of punches and dies formed on uniform rectangular plates, the combination comprising: a pair of identical punch and die holders each adapted to be secured to one of the stationary bed and reciprocating head of a punch press, said holders having cooperating bushings and parallel guide pins journaled in said bushings to maintain alignment of said holders as said head reciprocates, each of said holders comprising a base with a planar medial surface bounded on opposite sides by parallel vertical faces defining shoulders, a pair of spaced guide blocks secured to the medial surface of each of said holders and located against a respective one of said shoulders said guide blocks having opposing parallel surfaces adapted to mate with opposite sides of said plates, a clamping member releasably secured to each of said guide blocks and of a size to extend beyond the parallel surfaces of the guide blocks toward each other and overlying said medial surfaces, said clamping members adapted to hold plates disposed between said guide blocks against said medial surfaces of said holders, a stop member projecting from said medial surface of each holder toward the rear thereof to define rearward limits for the location of said plates in said holders; and releasable locking means adapted to hold said plates in aligned position in said holders against said stop members.

2. In a die holder assembly adapted for the mounting of punches and dies formed on uniform, flat rectangular plates, the combination comprising: a pair of identical punch and die holders each adapted to be secured to one of the stationary bed and reciprocating head of a punch press and each having a planar medial surface, one of said holders having a pair of spaced guide posts projecting normal to said medial surface adjacent the rear thereof, the other of said holders including a pair of spaced openings with bushings to receive said guide posts, a pair of parallel guide blocks secured to the medial surface of each of said holders, said guide blocks being spaced apart a distance corresponding to the width of said plates, a clamping member disposed on each of said guide blocks and extending beyond said guide blocks toward each other over said medial surfaces, a stop projecting from said medial surface of each of said holders toward the rear thereof, releasable locking means for each holder including a rod normally biased to project into the space between said guide blocks adjacent the front of said holder, said holders being adapted to receive one of said plates between said guide blocks, beneath said clamping members and against said stop and to have said locking means hold said plate in such position against removal.

3. A die holder assembly in accordance with claim 2 wherein said guide blocks are secured to said holders by machine screws the heads of which project outwardly of said guide blocks, said clamping members are provided with bores that receive the heads of said machine screws to locate said clamping members on said guide blocks, and. bolts extend through said clamping members and said guide blocks and are threadedly received in said holders for tightening of said clamping members against said plates received in said holders.

4. In a die holder assembly adapted for the mounting of punches and dies formed on uniform rectangular plates, the combination comprising: a pair of identical punch and die holders each adapted to be secured to one of the stationary bed and reciprocating head of a punch press, said holders having cooperating bushings and parallel guide pins journaled in said bushings to maintain alignment of said holders as said head reciprocates, a pair of spaced guide blocks secured to each of said holders and having opposing parallel surfaces adapted to mate with opposite sides of said plates, a clamping member disposed on each of said guide blocks and extending beyond said guide blocks and toward each other, a stop on each of said holders between said guide blocks and toward the rear thereof, said holders each adapted to receive one of said plates between said guide blocks, beneath said clamping members, and against said stop, one of said guide blocks of each of said holders extending beyond the limits of said plate and having a transverse bore therethrough, a rod disposed in said bore, a spring lever anchored at one end to said guide block and engaging said rod adjacent its other end to urge said rod through said bore and thereby have an end of said rod extend beyond said guide block and hold said plate against said stop.

5. In a die holder assembly adapted for the mounting of punches and dies formed on uniform, flat rectangular plates, the combination comprising: a die holder adapted to be secured to the bed of a punch press and having a pair of spaced upright guide posts projecting therefrom adjacent the rear of said die holder; a punch holder adapted to be secured to the reciprocating head of the punch press and having a pair of spaced openings with bushings that journal said guide posts; each of said holders comprising a base with a planar medial surface bounded on opposite sides by parallel vertical faces, a plurality of upright, spaced parallel pins extending in two rows from said medial surface inwardly of said faces, a pair of guide blocks located on said pins of each of said holders and secured to said holders by machine screws, said guide blocks being disposed upon said medial surfaces and against said faces, a clamping plate on each of said guide blocks and having openings to receive the heads of said machine screws, said clamping plates being of a size to extend beyond said guide blocks and overlay said medial surfaces, a bolt extending through each of said clamping plates and respective guide blocks and threadedly received in said base plate, a stop projecting from said medial surface of said holder toward the rear thereof, and a releasable locking mechanism comprising a rod disposed in .a transverse bore in one of said guide blocks and of a length sufficient to project from both ends thereof, and a spring lever anchored at one end to said guide block and engaging said rod to urge said rod to a position in which an end thereof extends toward the opposite guide block, whereby said rectangular plates are received in said holders between said guide blocks, beneath said clamping members, and between said stops and rods of said locking mechanisms.

6. A die holder assembly in accordance with claim 1 wherein said guide blocks are secured to said holders by machine screws, said clamping members have openings which receive the heads of said machine screws and locate said clamping members, and a bolt extends through each of said clamping members and respective guide block and is threadedly received in said base.

References Cited UNITED STATES PATENTS 1,202,175 10/1916 Foote 76-107 X 2,163,229 6/1939 Knebel 77-62 2,364,401 12/1944 Stellin 83-698 X 2,387,027 10/1945 Jackson 83698 X 2,545,560 3/1951 Scott 83-698 X 3,104,574 9/1963 Anderson et a1. 83-685 X 3,245,296 4/1966 Valenti 83-698 X FOREIGN PATENTS 656,738 2/ 1938 Germany.

WILLIAM W. DYER, JR., Primary Examiner. JAMES M. MEISTER, Examiner. 

1. IN A DIE HOLDER ASSEMBLY ADAPTED FOR THE MOUNTING OF PUNCHES AND DIES FORMED ON UNIFROM RECTANGULAR PLATES, THE COMBINATION COMPRISING: A PAIR OF IDENTICAL PUNCH AND DIE HOLDERS EACH ADAPTED TO BE SECURED TO ONE OF THE STATIONARY BED AND RECIPROCATING HEAD OF A PUNCH PRESS, SAID HOLDERS HAVING COOPERATING BUSHINGS AND PARALLEL GUIDE PINS JOURNALED IN SAID BUSHINGS TO MAINTAIN ALIGNMENT OF SAID HOLDERS AS SAID HEAD RECIPROCATES, EACH OF SAID HOLDERS COMPRISING A BASE WITH A PLANAR MEDIAL SURFACE BOUNDED ON OPPOSITE SIDES BY PARALLEL VERTICAL FACES DEFINING SHOULDERS, A PAIR OF SPACED GUIDE BLOCKS SECURED TO THE MEDIAL SURFACE OF EACH OF SAID HOLDERS AND LOCATED AGAINST A RESPECTIVE ONE OF SAID SHOULDERS SAID GUIDE BLOCKS HAVING OPPOSING PARALLEL SURFACES ADAPTED TO MATE WITH OPPOSITE SIDES OF SAID PLATES, A CLAMPING MEMBER RELEASABLY SECURED TO EACH OF SAID GUIDE BLOCKS AND OF A SIZE TO EXTEND BEYOND THE PARALLEL SURFACES OF THE GUIDE BLOCKS TOWARD EACH OTHER AND OVERLYING SAID MEDIAL SURFACES, SAID CLAMPING MEMBERS ADAPTED TO HOLD PLATES DISPOSED BETWEEN SAID GUIDE BLOCKS AGAINST SAID MEDIAL SURFACES OF SAID HOLDERS, A STOP MEMBER PROJECTING FROM SAID MEDIAL SURFACE OF EACH HOLDER TOWARD THE REAR THEREOF TO DEFINE REARWARD LIMITS FOR THE LOCATION OF SAID PLATES IN SAID HOLDERS; AND RELEASABLE LOCKING MEANS ADAPTED TO HOLD SAID PLATES IN ALIGNED POSITION IN SAID HOLDERS AGAINST SAID STOP MEMBERS. 